[3][4] In the human brain, the synaptic protein NLGN4 is primarily expressed in the cerebral cortex.

[5] This gene encodes a member of the neuroligin family of neuronal cell surface proteins.

Neuroligins may act as splice site-specific ligands for beta-neurexins and may be involved in the formation and remodeling of central nervous system synapses.

The encoded protein interacts with discs, large (Drosophila) homolog 4 (DLG4).

Two transcript variants encoding the same protein have been identified for this gene.